Tom worked very hard,  ______ that he would be able to buy a car of his own in two years.

A．hoped

B．to hope

C．hoping

D．and hoping

导致类风湿性关节炎出现低热、乏力等全身症状的主要细胞因子是（）

A.IL-1

B.IL-6

C.IL-2

D.IL-8

E.TNF-α